Merge branch 'unstable' of https://git01.codeplex.com/z3 into fpa-api

src/api/python/z3.py

@@ -899,6 +899,7 @@ def _coerce_expr_merge(s, a):
             return s
         else:
             if __debug__:
+                _z3_assert(s1.ctx == s.ctx, "context mismatch")
                 _z3_assert(False, "sort mismatch")
     else:
         return s
@@ -1459,9 +1460,18 @@ def And(*args):
     >>> And(P)
     And(p__0, p__1, p__2, p__3, p__4)
     """
+    last_arg = None
+    if len(args) > 0:
+        last_arg = args[len(args)-1]
+    if isinstance(last_arg, Context):
+        ctx = args[len(args)-1]
+        args = args[:len(args)-1]
+    else:
+        ctx = main_ctx()
     args = _get_args(args)
-    ctx   = _ctx_from_ast_arg_list(args)
+    ctx_args  = _ctx_from_ast_arg_list(args, ctx)
     if __debug__:
+        _z3_assert(ctx_args == None or ctx_args == ctx, "context mismatch")
         _z3_assert(ctx != None, "At least one of the arguments must be a Z3 expression or probe")
     if _has_probe(args):
         return _probe_and(args, ctx)
@@ -1480,9 +1490,18 @@ def Or(*args):
     >>> Or(P)
     Or(p__0, p__1, p__2, p__3, p__4)
     """
+    last_arg = None
+    if len(args) > 0:
+        last_arg = args[len(args)-1]
+    if isinstance(last_arg, Context):
+        ctx = args[len(args)-1]
+        args = args[:len(args)-1]
+    else:
+        ctx = main_ctx()
     args = _get_args(args)
-    ctx   = _ctx_from_ast_arg_list(args)
+    ctx_args  = _ctx_from_ast_arg_list(args, ctx)
     if __debug__:
+        _z3_assert(ctx_args == None or ctx_args == ctx, "context mismatch")
         _z3_assert(ctx != None, "At least one of the arguments must be a Z3 expression or probe")
     if _has_probe(args):
         return _probe_or(args, ctx)
@@ -4128,6 +4147,7 @@ class Datatype:
         """
         if __debug__:
             _z3_assert(isinstance(name, str), "String expected")
+            _z3_assert(name != "", "Constructor name cannot be empty")
         return self.declare_core(name, "is_" + name, *args)
 
     def __repr__(self):

src/ast/dl_decl_plugin.cpp

@@ -601,6 +601,22 @@ namespace datalog {
                 result = mk_compare(OP_DL_LT, m_lt_sym, domain);
                 break;   
 
+            case OP_DL_REP: {
+                if (!check_domain(0, 0, num_parameters) ||
+                    !check_domain(1, 1, arity)) return 0;
+                func_decl_info info(m_family_id, k, 0, 0);
+                result = m_manager->mk_func_decl(symbol("rep"), 1, domain, range, info);
+                break;
+            }
+                
+            case OP_DL_ABS: {
+                if (!check_domain(0, 0, num_parameters) ||
+                    !check_domain(1, 1, arity)) return 0;
+                func_decl_info info(m_family_id, k, 0, 0);
+                result = m_manager->mk_func_decl(symbol("abs"), 1, domain, range, info);
+                break;
+            }
+
             default:
                 m_manager->raise_exception("operator not recognized");
                 return 0;

src/ast/dl_decl_plugin.h

@@ -48,6 +48,8 @@ namespace datalog {
         OP_RA_CLONE,
         OP_DL_CONSTANT,
         OP_DL_LT,
+        OP_DL_REP,
+        OP_DL_ABS,
         LAST_RA_OP
     };
     

src/ast/scoped_proof.h

@@ -17,7 +17,7 @@ Revision History:
 
 --*/
 #ifndef _SCOPED_PROOF__H_
-#define _SCOPED_PROOF_H_
+#define _SCOPED_PROOF__H_
 
 #include "ast.h"
 

src/cmd_context/pdecl.cpp

@@ -189,7 +189,7 @@ class psort_app : public psort {
         m.inc_ref(d);
         m.inc_ref(num_args, args);
         SASSERT(num_args == m_decl->get_num_params() || m_decl->has_var_params());
-        DEBUG_CODE(for (unsigned i = 0; i < num_params; i++) args[i]->check_num_params(this););
+        DEBUG_CODE(if (num_args == num_params) { for (unsigned i = 0; i < num_params; i++) args[i]->check_num_params(this); });
     }
 
     virtual void finalize(pdecl_manager & m) { 

src/duality/duality.h

@@ -29,7 +29,7 @@ using namespace stl_ext;
 
 namespace Duality {
 
-  class implicant_solver;
+  struct implicant_solver;
 
   /* Generic operations on Z3 formulas */
 
@@ -253,6 +253,27 @@ protected:
         }
 
         void assert_axiom(const expr &axiom){
+#if 1
+	  // HACK: large "distict" predicates can kill the legacy SMT solver.
+	  // encode them with a UIF
+	  if(axiom.is_app() && axiom.decl().get_decl_kind() == Distinct)
+	    if(axiom.num_args() > 10){
+	      sort s = axiom.arg(0).get_sort();
+	      std::vector<sort> sv;
+	      sv.push_back(s);
+	      int nargs = axiom.num_args();
+	      std::vector<expr> args(nargs);
+	      func_decl f = ctx->fresh_func_decl("@distinct",sv,ctx->int_sort());
+	      for(int i = 0; i < nargs; i++){
+		expr a = axiom.arg(i);
+		expr new_cnstr = f(a) == ctx->int_val(i);
+		args[i] = new_cnstr;
+	      }
+	      expr cnstr = ctx->make(And,args);
+	      islvr->AssertInterpolationAxiom(cnstr);
+	      return;
+	    }
+#endif
             islvr->AssertInterpolationAxiom(axiom);
         }
 

src/duality/duality_solver.cpp

@@ -100,6 +100,7 @@ namespace Duality {
   };
 
    Reporter *CreateStdoutReporter(RPFP *rpfp);
+  Reporter *CreateConjectureFileReporter(RPFP *rpfp, const std::string &fname);
   
   /** Object we throw in case of catastrophe. */
 
@@ -125,6 +126,7 @@ namespace Duality {
     {
       rpfp = _rpfp;
       reporter = 0;
+      conj_reporter = 0;
       heuristic = 0;
       unwinding = 0;
       FullExpand = false;
@@ -274,6 +276,7 @@ namespace Duality {
 
     RPFP *rpfp;                          // the input RPFP 
     Reporter *reporter;                  // object for logging
+    Reporter *conj_reporter;             // object for logging conjectures
     Heuristic *heuristic;                // expansion heuristic
     context &ctx;                        // Z3 context
     solver &slvr;                        // Z3 solver
@@ -297,6 +300,7 @@ namespace Duality {
     int last_decisions;
     hash_set<Node *> overapproxes;
     std::vector<Proposer *> proposers;
+    std::string ConjectureFile;
 
 #ifdef BOUNDED
     struct Counter {
@@ -310,6 +314,7 @@ namespace Duality {
     /** Solve the problem. */
     virtual bool Solve(){
       reporter = Report ? CreateStdoutReporter(rpfp) : new Reporter(rpfp);
+      conj_reporter = ConjectureFile.empty() ? 0 : CreateConjectureFileReporter(rpfp,ConjectureFile); 
 #ifndef LOCALIZE_CONJECTURES
       heuristic = !cex.get_tree() ? new Heuristic(rpfp) : new ReplayHeuristic(rpfp,cex);
 #else
@@ -340,6 +345,8 @@ namespace Duality {
       delete heuristic;
       // delete unwinding; // keep the unwinding for future mining of predicates
       delete reporter;
+      if(conj_reporter)
+	delete conj_reporter;
       for(unsigned i = 0; i < proposers.size(); i++)
 	delete proposers[i];
       return res;
@@ -449,6 +456,9 @@ namespace Duality {
       if(option == "recursion_bound"){
         return SetIntOption(RecursionBound,value);
       }
+      if(option == "conjecture_file"){
+	ConjectureFile = value;
+      }
       return false;
     }
     
@@ -728,6 +738,13 @@ namespace Duality {
       return ctx.constant(name.c_str(),ctx.bool_sort());
     }
 
+    /** Make a boolean variable to act as a "marker" for a pair of nodes. */
+    expr NodeMarker(Node *node1, Node *node2){
+      std::string name = std::string("@m_") + string_of_int(node1->number);
+      name += std::string("_") + string_of_int(node2->number);
+      return ctx.constant(name.c_str(),ctx.bool_sort());
+    }
+
     /** Union the annotation of dst into src. If with_markers is
 	true, we conjoin the annotation formula of dst with its
 	marker. This allows us to discover which disjunct is
@@ -1136,19 +1153,19 @@ namespace Duality {
     }
   
     
-    void GenNodeSolutionWithMarkersAux(Node *node, RPFP::Transformer &annot, expr &marker_disjunction){
+    void GenNodeSolutionWithMarkersAux(Node *node, RPFP::Transformer &annot, expr &marker_disjunction, Node *other_node){
 #ifdef BOUNDED
       if(RecursionBound >= 0 && NodePastRecursionBound(node))
 	return;
 #endif
       RPFP::Transformer temp = node->Annotation;
-      expr marker = NodeMarker(node);
+      expr marker = (!other_node) ? NodeMarker(node) : NodeMarker(node, other_node);
       temp.Formula = (!marker || temp.Formula);
       annot.IntersectWith(temp);
       marker_disjunction = marker_disjunction || marker;
     }
 
-    bool GenNodeSolutionWithMarkers(Node *node, RPFP::Transformer &annot, bool expanded_only = false){
+    bool GenNodeSolutionWithMarkers(Node *node, RPFP::Transformer &annot, bool expanded_only = false, Node *other_node = 0){
       bool res = false;
       annot.SetFull();
       expr marker_disjunction = ctx.bool_val(false);
@@ -1156,7 +1173,7 @@ namespace Duality {
       for(unsigned j = 0; j < insts.size(); j++){
 	Node *node = insts[j];
 	if(indset->Contains(insts[j])){
-	  GenNodeSolutionWithMarkersAux(node, annot, marker_disjunction); res = true;
+	  GenNodeSolutionWithMarkersAux(node, annot, marker_disjunction, other_node); res = true;
 	}
       }
       annot.Formula = annot.Formula && marker_disjunction;
@@ -1253,7 +1270,7 @@ namespace Duality {
 	  Node *inst = insts[k];
 	  if(indset->Contains(inst)){
 	    if(checker->Empty(node) || 
-	       eq(lb ? checker->Eval(lb,NodeMarker(inst)) : checker->dualModel.eval(NodeMarker(inst)),ctx.bool_val(true))){
+	       eq(lb ? checker->Eval(lb,NodeMarker(inst)) : checker->dualModel.eval(NodeMarker(inst,node)),ctx.bool_val(true))){
 	      candidate.Children.push_back(inst);
 	      goto next_child;
 	    }
@@ -1336,7 +1353,7 @@ namespace Duality {
       for(unsigned j = 0; j < edge->Children.size(); j++){
 	Node *oc = edge->Children[j];
 	Node *nc = gen_cands_edge->Children[j];
-        GenNodeSolutionWithMarkers(oc,nc->Annotation,true);
+        GenNodeSolutionWithMarkers(oc,nc->Annotation,true,nc);
       }
       checker->AssertEdge(gen_cands_edge,1,true);
       return root;
@@ -1462,6 +1479,8 @@ namespace Duality {
     bool Update(Node *node, const RPFP::Transformer &fact, bool eager=false){
       if(!node->Annotation.SubsetEq(fact)){
 	reporter->Update(node,fact,eager);
+	if(conj_reporter)
+	  conj_reporter->Update(node,fact,eager);
 	indset->Update(node,fact);
 	updated_nodes.insert(node->map);
 	node->Annotation.IntersectWith(fact);
@@ -2201,7 +2220,7 @@ namespace Duality {
 #endif
 	    int expand_max = 1;
 	    if(0&&duality->BatchExpand){
-	      int thing = stack.size() * 0.1;
+              int thing = stack.size() / 10; // * 0.1;
 	      expand_max = std::max(1,thing);
 	      if(expand_max > 1)
 		std::cout << "foo!\n";
@@ -3043,6 +3062,7 @@ namespace Duality {
     };
   };
 
+  static int stop_event = -1;
 
   class StreamReporter : public Reporter {
     std::ostream &s;
@@ -3052,6 +3072,9 @@ namespace Duality {
     int event;
     int depth;
     void ev(){
+      if(stop_event == event){
+	std::cout << "stop!\n";
+      }
       s << "[" << event++ << "]" ;
     }
     virtual void Extend(RPFP::Node *node){
@@ -3129,4 +3152,28 @@ namespace Duality {
   Reporter *CreateStdoutReporter(RPFP *rpfp){
     return new StreamReporter(rpfp, std::cout);
   }
+
+  class ConjectureFileReporter : public Reporter {
+    std::ofstream s;
+  public:
+    ConjectureFileReporter(RPFP *_rpfp, const std::string &fname)
+      : Reporter(_rpfp), s(fname.c_str()) {}
+    virtual void Update(RPFP::Node *node, const RPFP::Transformer &update, bool eager){
+      s << "(define-fun " << node->Name.name() << " (";
+      for(unsigned i = 0; i < update.IndParams.size(); i++){
+	if(i != 0)
+	  s << " ";
+	s << "(" << update.IndParams[i] << " " << update.IndParams[i].get_sort() << ")";
       }
+      s << ") Bool \n";
+      s << update.Formula << ")\n";
+      s << std::endl;
+    }
+  };
+
+  Reporter *CreateConjectureFileReporter(RPFP *rpfp, const std::string &fname){
+    return new ConjectureFileReporter(rpfp, fname);
+  }
+
+}
+

src/duality/duality_wrapper.h

@@ -397,6 +397,11 @@ namespace Duality {
       
       sort array_domain() const;
       sort array_range() const;
+
+      friend std::ostream & operator<<(std::ostream & out, sort const & m){
+	m.ctx().print_expr(out,m);
+	return out;
+      }
     };
 
     

src/interp/iz3base.cpp

@@ -260,7 +260,7 @@ void iz3base::check_interp(const std::vector<ast> &itps, std::vector<ast> &theor
 #endif
 }
 
-bool iz3base::is_sat(const std::vector<ast> &q, ast &_proof){
+bool iz3base::is_sat(const std::vector<ast> &q, ast &_proof, std::vector<ast> &vars){
 
   params_ref p;
   p.set_bool("proof", true); // this is currently useless
@@ -277,6 +277,15 @@ bool iz3base::is_sat(const std::vector<ast> &q, ast &_proof){
     ::ast *proof = s.get_proof();
     _proof = cook(proof);
   }
+  else if(vars.size()) {
+    model_ref(_m);
+    s.get_model(_m);
+    for(unsigned i = 0; i < vars.size(); i++){
+      expr_ref r(m());
+      _m.get()->eval(to_expr(vars[i].raw()),r,true);
+      vars[i] = cook(r.get());
+    }
+  }
   dealloc(m_solver);
   return res != l_false;
 }

src/interp/iz3base.h

@@ -113,7 +113,7 @@ class iz3base : public iz3mgr, public scopes {
   void check_interp(const std::vector<ast> &itps, std::vector<ast> &theory);
 
   /** For convenience -- is this formula SAT? */
-  bool is_sat(const std::vector<ast> &consts, ast &_proof);
+  bool is_sat(const std::vector<ast> &consts, ast &_proof, std::vector<ast> &vars);
 
   /** Interpolator for clauses, to be implemented */
   virtual void interpolate_clause(std::vector<ast> &lits, std::vector<ast> &itps){

src/interp/iz3hash.h

@@ -29,6 +29,10 @@ Revision History:
 #ifndef IZ3_HASH_H
 #define IZ3_HASH_H
 
+#ifdef _WINDOWS
+#pragma warning(disable:4267)
+#endif
+
 #include <string>
 #include <vector>
 #include <iterator>

src/interp/iz3mgr.h

@@ -387,10 +387,13 @@ class iz3mgr  {
     return UnknownTheory;
   }
 
-  enum lemma_kind {FarkasKind,Leq2EqKind,Eq2LeqKind,GCDTestKind,AssignBoundsKind,EqPropagateKind,UnknownKind};
+  enum lemma_kind {FarkasKind,Leq2EqKind,Eq2LeqKind,GCDTestKind,AssignBoundsKind,EqPropagateKind,ArithMysteryKind,UnknownKind};
 
   lemma_kind get_theory_lemma_kind(const ast &proof){
     symb s = sym(proof);
+    if(s->get_num_parameters() < 2) {
+      return ArithMysteryKind;  // Bad -- Z3 hasn't told us
+    }
     ::symbol p0;
     bool ok = s->get_parameter(1).is_symbol(p0);
     if(!ok) return UnknownKind;

src/interp/iz3proof_itp.cpp

@@ -607,7 +607,29 @@ class iz3proof_itp_impl : public iz3proof_itp {
     return res;
   }
 
+  ast distribute_coeff(const ast &coeff, const ast &s){
+    if(sym(s) == sum){
+      if(sym(arg(s,2)) == sum)
+	return make(sum,
+		    distribute_coeff(coeff,arg(s,0)),
+		    make_int(rational(1)),
+		    distribute_coeff(make(Times,coeff,arg(s,1)), arg(s,2)));
+      else
+	return make(sum,
+		    distribute_coeff(coeff,arg(s,0)),
+		    make(Times,coeff,arg(s,1)),
+		    arg(s,2));
+    }
+    if(op(s) == Leq && arg(s,1) == make_int(rational(0)) && arg(s,2) == make_int(rational(0)))
+      return s;
+    return make(sum,make(Leq,make_int(rational(0)),make_int(rational(0))),coeff,s);
+  }
+
   ast simplify_sum(std::vector<ast> &args){
+    if(args[1] != make_int(rational(1))){
+      if(sym(args[2]) == sum)
+	return make(sum,args[0],make_int(rational(1)),distribute_coeff(args[1],args[2]));
+    }
     ast Aproves = mk_true(), Bproves = mk_true();
     ast ineq = destruct_cond_ineq(args[0],Aproves,Bproves);
     if(!is_normal_ineq(ineq)) throw cannot_simplify();
@@ -757,6 +779,22 @@ class iz3proof_itp_impl : public iz3proof_itp {
       ast Bcond = my_implies(Bproves1,my_and(Aproves1,z3_simplify(ineq2)));
       //      if(!is_true(Aproves1) || !is_true(Bproves1))
       //	std::cout << "foo!\n";;
+      if(y == make_int(rational(0)) && op(x) == Plus && num_args(x) == 2){
+	if(get_term_type(arg(x,0)) == LitA){
+	  ast iter = z3_simplify(make(Plus,arg(x,0),get_ineq_rhs(xleqy)));
+	  ast rewrite1 = make_rewrite(LitA,pos_add(0,top_pos),Acond,make(Equal,arg(x,0),iter));
+	  iter = make(Plus,iter,arg(x,1));
+	  ast rewrite2 = make_rewrite(LitB,top_pos,Bcond,make(Equal,iter,y));
+	  return chain_cons(chain_cons(mk_true(),rewrite1),rewrite2);
+	}
+	if(get_term_type(arg(x,1)) == LitA){
+	  ast iter = z3_simplify(make(Plus,arg(x,1),get_ineq_rhs(xleqy)));
+	  ast rewrite1 = make_rewrite(LitA,pos_add(1,top_pos),Acond,make(Equal,arg(x,1),iter));
+	  iter = make(Plus,arg(x,0),iter);
+	  ast rewrite2 = make_rewrite(LitB,top_pos,Bcond,make(Equal,iter,y));
+	  return chain_cons(chain_cons(mk_true(),rewrite1),rewrite2);
+	}
+      }
       if(get_term_type(x) == LitA){
 	ast iter = z3_simplify(make(Plus,x,get_ineq_rhs(xleqy)));
 	ast rewrite1 = make_rewrite(LitA,top_pos,Acond,make(Equal,x,iter));
@@ -1014,6 +1052,7 @@ class iz3proof_itp_impl : public iz3proof_itp {
       coeff = argpos ? make_int(rational(-1)) : make_int(rational(1));
       break;
     case Not:
+      coeff = make_int(rational(-1));
     case Plus:
       break;
     case Times:
@@ -2568,6 +2607,10 @@ class iz3proof_itp_impl : public iz3proof_itp {
       break;
     default: { // mixed equality
       if(get_term_type(x) == LitMixed || get_term_type(y) == LitMixed){
+	if(y == make_int(rational(0)) && op(x) == Plus && num_args(x) == 2){
+	  // std::cerr << "WARNING: untested case in leq2eq\n";
+	}
+	else {
 	  // std::cerr << "WARNING: mixed term in leq2eq\n"; 
 	  std::vector<ast> lits;
 	  lits.push_back(con);
@@ -2575,6 +2618,7 @@ class iz3proof_itp_impl : public iz3proof_itp {
 	  lits.push_back(make(Not,yleqx));
 	  return make_axiom(lits);
 	}
+      }
       std::vector<ast> conjs; conjs.resize(3);
       conjs[0] = mk_not(con);
       conjs[1] = xleqy;
@@ -2655,8 +2699,13 @@ class iz3proof_itp_impl : public iz3proof_itp {
   };
 
   std::vector<LocVar> localization_vars;         // localization vars in order of creation
+
+  struct locmaps {
     hash_map<ast,ast> localization_map;            // maps terms to their localization vars
     hash_map<ast,ast> localization_pf_map;         // maps terms to proofs of their localizations
+  };
+  
+  hash_map<prover::range,locmaps> localization_maps_per_range;
 
   /* "localize" a term e to a given frame range, creating new symbols to
      represent non-local subterms. This returns the localized version e_l,
@@ -2677,7 +2726,24 @@ class iz3proof_itp_impl : public iz3proof_itp {
       return make(Equal,x,y);
   }
 
+  bool range_is_global(const prover::range &r){
+    if(pv->range_contained(r,rng))
+      return false;
+    if(!pv->ranges_intersect(r,rng))
+      return false;
+    return true;
+  }
+
   ast localize_term(ast e, const prover::range &rng, ast &pf){
+
+    // we need to memoize this function separately for A, B and global
+    prover::range map_range = rng;
+    if(range_is_global(map_range))
+      map_range = pv->range_full();
+    locmaps &maps = localization_maps_per_range[map_range];
+    hash_map<ast,ast> &localization_map = maps.localization_map;
+    hash_map<ast,ast> &localization_pf_map = maps.localization_pf_map;
+
     ast orig_e = e;
     pf = make_refl(e);  // proof that e = e
 
@@ -2764,6 +2830,21 @@ class iz3proof_itp_impl : public iz3proof_itp {
     ast bar = make_assumption(frame,foo);
     pf = make_transitivity(new_var,e,orig_e,bar,pf);
     localization_pf_map[orig_e] = pf;
+
+    // HACK: try to bias this term in the future
+    if(!pv->range_is_full(rng)){
+      prover::range rf = pv->range_full();
+      locmaps &fmaps = localization_maps_per_range[rf];
+      hash_map<ast,ast> &flocalization_map = fmaps.localization_map;
+      hash_map<ast,ast> &flocalization_pf_map = fmaps.localization_pf_map;
+      // if(flocalization_map.find(orig_e) == flocalization_map.end())
+	{
+	  flocalization_map[orig_e] = new_var;
+	  flocalization_pf_map[orig_e] = pf;
+	}
+    }
+      
+    
     return new_var;
   }
 

src/interp/iz3scopes.h

@@ -23,6 +23,7 @@ Revision History:
 
 #include <vector>
 #include <limits.h>
+#include "iz3hash.h"
 
 class scopes {
 
@@ -63,6 +64,11 @@ class scopes {
 	  return rng.hi < rng.lo;
   }
 
+  /** is this range full? */
+  bool range_is_full(const range &rng){
+    return rng.lo == SHRT_MIN && rng.hi == SHRT_MAX;
+  }
+
   /** return an empty range */
   range range_empty(){
      range res;
@@ -194,4 +200,23 @@ class scopes {
 
 
 };
+
+// let us hash on ranges
+
+#ifndef FULL_TREE
+namespace hash_space {
+  template <>
+  class hash<scopes::range> {
+  public:
+    size_t operator()(const scopes::range &p) const {
+      return (size_t)p.lo + (size_t)p.hi;
+    }
+  };
+}
+
+inline bool operator==(const scopes::range &x, const scopes::range &y){
+  return x.lo == y.lo && x.hi == y.hi;
+}
+#endif
+
 #endif

src/interp/iz3translate.cpp

@@ -1058,36 +1058,66 @@ public:
   }
 
 
+  rational get_first_coefficient(const ast &t, ast &v){
+    if(op(t) == Plus){
+      unsigned best_id = UINT_MAX;
+      rational best_coeff(0);
+      int nargs = num_args(t);
+      for(int i = 0; i < nargs; i++)
+	if(op(arg(t,i)) != Numeral){
+	  ast lv = get_linear_var(arg(t,i));
+	  unsigned id = ast_id(lv);
+	  if(id < best_id) {
+	    v = lv;
+	    best_id = id;
+	    best_coeff = get_coeff(arg(t,i));
+	  }
+	}
+      return best_coeff;
+    }
+    else
+      if(op(t) != Numeral)
+	return(get_coeff(t));
+    return rational(0);
+  }
+
   ast divide_inequalities(const ast &x, const ast&y){
-    std::vector<rational> xcoeffs,ycoeffs;
+    ast xvar, yvar;
-    get_linear_coefficients(arg(x,1),xcoeffs);
+    rational xcoeff = get_first_coefficient(arg(x,0),xvar);
-    get_linear_coefficients(arg(y,1),ycoeffs);
+    rational ycoeff = get_first_coefficient(arg(y,0),yvar);
-    if(xcoeffs.size() != ycoeffs.size() || xcoeffs.size() == 0)
+    if(xcoeff == rational(0) || ycoeff == rational(0) || xvar != yvar)
+      throw "bad assign-bounds lemma";
+    rational ratio = xcoeff/ycoeff;
+    if(denominator(ratio) != rational(1))
       throw "bad assign-bounds lemma";
-    rational ratio = xcoeffs[0]/ycoeffs[0];
     return make_int(ratio); // better be integer!
   }
 
   ast AssignBounds2Farkas(const ast &proof, const ast &con){
     std::vector<ast> farkas_coeffs;
     get_assign_bounds_coeffs(proof,farkas_coeffs);
-    std::vector<ast> lits;
     int nargs = num_args(con);
     if(nargs != (int)(farkas_coeffs.size()))
       throw "bad assign-bounds theory lemma";
 #if 0
-    for(int i = 1; i < nargs; i++)
+    if(farkas_coeffs[0] != make_int(rational(1)))
-      lits.push_back(mk_not(arg(con,i)));
+      farkas_coeffs[0] = make_int(rational(1));
-    ast sum = sum_inequalities(farkas_coeffs,lits);
-    ast conseq = rhs_normalize_inequality(arg(con,0));
-    ast d = divide_inequalities(sum,conseq);
-    std::vector<ast> my_coeffs;
-    my_coeffs.push_back(d);
-    for(unsigned i = 0; i < farkas_coeffs.size(); i++)
-      my_coeffs.push_back(farkas_coeffs[i]);
 #else
-    std::vector<ast> my_coeffs;
+    std::vector<ast> lits, lit_coeffs;
+    for(int i = 1; i < nargs; i++){
+      lits.push_back(mk_not(arg(con,i)));
+      lit_coeffs.push_back(farkas_coeffs[i]);
+    }
+    ast sum = normalize_inequality(sum_inequalities(lit_coeffs,lits));
+    ast conseq = normalize_inequality(arg(con,0));
+    ast d = divide_inequalities(sum,conseq);
+#if 0
+    if(d != farkas_coeffs[0])
+      std::cout << "wow!\n";
 #endif
+    farkas_coeffs[0] = d;
+#endif
+    std::vector<ast> my_coeffs;
     std::vector<ast> my_cons;
     for(int i = 1; i < nargs; i++){
       my_cons.push_back(mk_not(arg(con,i)));
@@ -1107,10 +1137,27 @@ public:
   ast AssignBoundsRule2Farkas(const ast &proof, const ast &con, std::vector<Iproof::node> prems){
     std::vector<ast> farkas_coeffs;
     get_assign_bounds_rule_coeffs(proof,farkas_coeffs);
-    std::vector<ast> lits;
     int nargs = num_prems(proof)+1;
     if(nargs != (int)(farkas_coeffs.size()))
       throw "bad assign-bounds theory lemma";
+#if 0
+    if(farkas_coeffs[0] != make_int(rational(1)))
+      farkas_coeffs[0] = make_int(rational(1));
+#else
+    std::vector<ast> lits, lit_coeffs;
+    for(int i = 1; i < nargs; i++){
+      lits.push_back(conc(prem(proof,i-1)));
+      lit_coeffs.push_back(farkas_coeffs[i]);
+    }
+    ast sum = normalize_inequality(sum_inequalities(lit_coeffs,lits));
+    ast conseq = normalize_inequality(con);
+    ast d = divide_inequalities(sum,conseq);
+#if 0
+    if(d != farkas_coeffs[0])
+      std::cout << "wow!\n";
+#endif
+    farkas_coeffs[0] = d;
+#endif
     std::vector<ast> my_coeffs;
     std::vector<ast> my_cons;
     for(int i = 1; i < nargs; i++){
@@ -1278,6 +1325,17 @@ public:
     return make(Plus,args);
   }
 
+  void get_sum_as_vector(const ast &t, std::vector<rational> &coeffs, std::vector<ast> &vars){
+    if(!(op(t) == Plus)){
+      coeffs.push_back(get_coeff(t));
+      vars.push_back(get_linear_var(t));
+    }
+    else {
+      int nargs = num_args(t);
+      for(int i = 0; i < nargs; i++)
+	get_sum_as_vector(arg(t,i),coeffs,vars);
+    }
+  }
 
   ast replace_summands_with_fresh_vars(const ast &t, hash_map<ast,ast> &map){
     if(op(t) == Plus){
@@ -1294,6 +1352,99 @@ public:
     return map[t];
   }
 
+  rational lcd(const std::vector<rational> &rats){
+    rational res = rational(1);
+    for(unsigned i = 0; i < rats.size(); i++){
+      res = lcm(res,denominator(rats[i]));
+    }
+    return res;
+  } 
+
+  Iproof::node reconstruct_farkas_with_dual(const std::vector<ast> &prems, const std::vector<Iproof::node> &pfs, const ast &con){
+    int nprems = prems.size();
+    std::vector<ast> npcons(nprems);
+    hash_map<ast,ast> pain_map; // not needed
+    for(int i = 0; i < nprems; i++){
+      npcons[i] = painfully_normalize_ineq(conc(prems[i]),pain_map);
+      if(op(npcons[i]) == Lt){
+	ast constval = z3_simplify(make(Sub,arg(npcons[i],1),make_int(rational(1))));
+	npcons[i] = make(Leq,arg(npcons[i],0),constval);
+      }
+    }
+    ast ncon = painfully_normalize_ineq(mk_not(con),pain_map);
+    npcons.push_back(ncon);
+
+    hash_map<ast,ast> dual_map;
+    std::vector<ast> cvec, vars_seen;
+    ast rhs = make_real(rational(0));
+    for(unsigned i = 0; i < npcons.size(); i++){
+      ast c= mk_fresh_constant("@c",real_type());
+      cvec.push_back(c);
+      ast lhs = arg(npcons[i],0);
+      std::vector<rational> coeffs;
+      std::vector<ast> vars;
+      get_sum_as_vector(lhs,coeffs,vars);
+      for(unsigned j = 0; j < coeffs.size(); j++){
+	rational coeff = coeffs[j];
+	ast var = vars[j];
+	if(dual_map.find(var) == dual_map.end()){
+	  dual_map[var] = make_real(rational(0));
+	  vars_seen.push_back(var);
+	}
+	ast foo = make(Plus,dual_map[var],make(Times,make_real(coeff),c));
+	dual_map[var] = foo;
+      }
+      rhs = make(Plus,rhs,make(Times,c,arg(npcons[i],1)));
+    }
+    std::vector<ast> cnstrs;
+    for(unsigned i = 0; i < vars_seen.size(); i++)
+      cnstrs.push_back(make(Equal,dual_map[vars_seen[i]],make_real(rational(0))));
+    cnstrs.push_back(make(Leq,rhs,make_real(rational(0))));
+    for(unsigned i = 0; i < cvec.size() - 1; i++)
+      cnstrs.push_back(make(Geq,cvec[i],make_real(rational(0))));
+    cnstrs.push_back(make(Equal,cvec.back(),make_real(rational(1))));
+    ast new_proof;
+
+    // greedily reduce the core
+    for(unsigned i = 0; i < cvec.size() - 1; i++){
+      std::vector<ast> dummy;
+      cnstrs.push_back(make(Equal,cvec[i],make_real(rational(0))));
+      if(!is_sat(cnstrs,new_proof,dummy))
+	cnstrs.pop_back();
+    }
+
+    std::vector<ast> vals = cvec;
+    if(!is_sat(cnstrs,new_proof,vals))
+      throw "Proof error!";
+    std::vector<rational> rat_farkas_coeffs;
+    for(unsigned i = 0; i < cvec.size(); i++){
+      ast bar = vals[i];
+      rational r;
+      if(is_numeral(bar,r))
+	rat_farkas_coeffs.push_back(r);
+      else
+	throw "Proof error!";
+    }
+    rational the_lcd = lcd(rat_farkas_coeffs);
+    std::vector<ast> farkas_coeffs;
+    std::vector<Iproof::node> my_prems;
+    std::vector<ast> my_pcons;
+    for(unsigned i = 0; i < prems.size(); i++){
+      ast fc = make_int(rat_farkas_coeffs[i] * the_lcd);
+      if(!(fc == make_int(rational(0)))){
+	farkas_coeffs.push_back(fc);
+	my_prems.push_back(pfs[i]);
+	my_pcons.push_back(conc(prems[i]));
+      }
+    }
+    farkas_coeffs.push_back(make_int(the_lcd));
+    my_prems.push_back(iproof->make_hypothesis(mk_not(con)));
+    my_pcons.push_back(mk_not(con));
+    
+    Iproof::node res = iproof->make_farkas(mk_false(),my_prems,my_pcons,farkas_coeffs);
+    return res;
+  }
+
   ast painfully_normalize_ineq(const ast &ineq, hash_map<ast,ast> &map){
     ast res = normalize_inequality(ineq);
     ast lhs = arg(res,0);
@@ -1318,7 +1469,8 @@ public:
     npcons.push_back(ncon);
     // ast assumps = make(And,pcons);
     ast new_proof;
-    if(is_sat(npcons,new_proof))
+    std::vector<ast> dummy;
+    if(is_sat(npcons,new_proof,dummy))
       throw "Proof error!";
     pfrule dk = pr(new_proof);
     int nnp = num_prems(new_proof);
@@ -1334,7 +1486,7 @@ public:
 	farkas_coeffs.push_back(make_int(rational(1)));
     }
     else
-      throw "cannot reconstruct farkas proof";
+      return reconstruct_farkas_with_dual(prems,pfs,con);
 
     for(int i = 0; i < nnp; i++){
       ast p = conc(prem(new_proof,i));
@@ -1348,7 +1500,7 @@ public:
 	my_pcons.push_back(mk_not(con));
       }
       else
-	throw "cannot reconstruct farkas proof";
+	return reconstruct_farkas_with_dual(prems,pfs,con);
     }
     Iproof::node res = iproof->make_farkas(mk_false(),my_prems,my_pcons,farkas_coeffs);
     return res;
@@ -1378,7 +1530,8 @@ public:
     npcons.push_back(ncon);
     // ast assumps = make(And,pcons);
     ast new_proof;
-    if(is_sat(npcons,new_proof))
+    std::vector<ast> dummy;
+    if(is_sat(npcons,new_proof,dummy))
       throw "Proof error!";
     pfrule dk = pr(new_proof);
     int nnp = num_prems(new_proof);
@@ -1408,7 +1561,7 @@ public:
 	my_pcons.push_back(mk_not(con));
       }
       else
-	throw "cannot reconstruct farkas proof";
+	return painfully_reconstruct_farkas(prems,pfs,con);
     }
     Iproof::node res = iproof->make_farkas(mk_false(),my_prems,my_pcons,farkas_coeffs);
     return res;
@@ -1433,6 +1586,12 @@ public:
     return res;
   }
 
+  ast ArithMysteryRule(const ast &con, const std::vector<ast> &prems, const std::vector<Iproof::node> &args){
+    // Hope for the best!
+    Iproof::node guess = reconstruct_farkas(prems,args,con);
+    return guess;
+  }
+
   struct CannotCombineEqPropagate {};
 
   void CombineEqPropagateRec(const ast &proof, std::vector<ast> &prems, std::vector<Iproof::node> &args, ast &eqprem){
@@ -1552,6 +1711,13 @@ public:
       if(dk == PR_MODUS_PONENS && expect_clause && op(con) == Or)
 	std::cout << "foo!\n";
 
+      // no idea why this shows up
+      if(dk == PR_MODUS_PONENS_OEQ)
+	if(conc(prem(proof,0)) == con){
+	  res = translate_main(prem(proof,0),expect_clause);
+	  return res;
+	}
+      
 #if 0
       if(1 && dk == PR_TRANSITIVITY && pr(prem(proof,1)) == PR_COMMUTATIVITY){
 	Iproof::node clause = translate_main(prem(proof,0),true);
@@ -1737,6 +1903,14 @@ public:
 	    res = EqPropagate(con,prems,args);
 	    break;
 	  }
+	  case ArithMysteryKind: {
+	    // Z3 hasn't told us what kind of lemma this is -- maybe we can guess
+	    std::vector<ast> prems(nprems);
+	    for(unsigned i = 0; i < nprems; i++)
+	      prems[i] = prem(proof,i);
+	    res = ArithMysteryRule(con,prems,args);
+	    break;
+	  }
 	  default:
 	    throw unsupported();
 	  }

src/math/polynomial/upolynomial_factorization.cpp

@@ -530,7 +530,7 @@ bool check_hansel_lift(z_manager & upm, numeral_vector const & C,
     upm.mul(A_lifted.size(), A_lifted.c_ptr(), B_lifted.size(), B_lifted.c_ptr(), test1);
     upm.sub(C.size(), C.c_ptr(), test1.size(), test1.c_ptr(), test1);
     to_zp_manager(br_upm, test1);
-    if (!test1.size() == 0) {
+    if (test1.size() != 0) {
         TRACE("polynomial::factorization::bughunt", 
             tout << "sage: R.<x> = ZZ['x']" << endl;
             tout << "sage: A = "; upm.display(tout, A); tout << endl;

src/model/model.cpp

@@ -133,7 +133,9 @@ bool model::eval(expr * e, expr_ref & result, bool model_completion) {
         ev(e, result);
         return true;
     }
-    catch (model_evaluator_exception &) {
+    catch (model_evaluator_exception & ex) {
+        (void)ex;
+        TRACE("model_evaluator", tout << ex.msg() << "\n";);
         return false;
     }
 }

src/muz/base/dl_context.h

@@ -278,6 +278,12 @@ namespace datalog {
 
         void register_variable(func_decl* var);
 
+        /*
+          Replace constants that have been registered as 
+          variables by de-Bruijn indices and corresponding
+          universal (if is_forall is true) or existential 
+          quantifier.
+         */
         expr_ref bind_variables(expr* fml, bool is_forall);
 
         /**

src/muz/base/fixedpoint_params.pyg

@@ -77,6 +77,7 @@ def_module_params('fixedpoint',
 			  ('mbqi', BOOL, True, 'DUALITY: use model-based quantifier instantion'),
 			  ('batch_expand', BOOL, False, 'DUALITY: use batch expansion'),
                           ('dump_aig', SYMBOL, '', 'Dump clauses in AIG text format (AAG) to the given file name'),
+			  ('conjecture_file', STRING, '', 'DUALITY: save conjectures to file'),
                           ))
 
 

src/muz/duality/duality_dl_interface.cpp

@@ -35,6 +35,7 @@ Revision History:
 #include "model_smt2_pp.h"
 #include "model_v2_pp.h"
 #include "fixedpoint_params.hpp"
+#include "used_vars.h"
 
 // template class symbol_table<family_id>;
 
@@ -164,6 +165,20 @@ lbool dl_interface::query(::expr * query) {
     clauses.push_back(e);
   }
   
+  std::vector<sort> b_sorts;
+  std::vector<symbol> b_names;
+  used_vars uv;
+  uv.process(query);
+  unsigned nuv = uv.get_max_found_var_idx_plus_1();
+  for(int i = nuv-1; i >= 0; i--){ // var indices are backward
+    ::sort * s = uv.get(i);
+    if(!s)
+      s = _d->ctx.m().mk_bool_sort(); // missing var, whatever
+    b_sorts.push_back(sort(_d->ctx,s));
+    b_names.push_back(symbol(_d->ctx,::symbol(i))); // names?
+  }
+
+#if 0
   // turn the query into a clause
   expr q(_d->ctx,m_ctx.bind_variables(query,false));
   
@@ -177,6 +192,9 @@ lbool dl_interface::query(::expr * query) {
     }
     q = q.arg(0);
   }
+#else
+  expr q(_d->ctx,query);
+#endif
 
   expr qc = implies(q,_d->ctx.bool_val(false));
   qc = _d->ctx.make_quant(Forall,b_sorts,b_names,qc);
@@ -211,6 +229,7 @@ lbool dl_interface::query(::expr * query) {
   rs->SetOption("use_underapprox",m_ctx.get_params().use_underapprox() ? "1" : "0");
   rs->SetOption("stratified_inlining",m_ctx.get_params().stratified_inlining() ? "1" : "0");
   rs->SetOption("batch_expand",m_ctx.get_params().batch_expand() ? "1" : "0");
+  rs->SetOption("conjecture_file",m_ctx.get_params().conjecture_file());
   unsigned rb = m_ctx.get_params().recursion_bound();
   if(rb != UINT_MAX){
     std::ostringstream os; os << rb;
@@ -350,7 +369,9 @@ void dl_interface::display_certificate_non_const(std::ostream& out) {
   if(_d->status == StatusModel){
     ast_manager &m = m_ctx.get_manager();
     model_ref md = get_model();
+    out << "(fixedpoint \n";
     model_smt2_pp(out, m, *md.get(), 0); 
+    out << ")\n";
   }
   else if(_d->status == StatusRefutation){
     out << "(derivation\n";

src/muz/transforms/dl_mk_coi_filter.cpp

@@ -200,7 +200,22 @@ namespace datalog {
             func_decl_set::iterator it = pruned_preds.begin();
             extension_model_converter* mc0 = alloc(extension_model_converter, m);
             for (; it != end; ++it) {
-                mc0->insert(*it, m.mk_true());
+                const rule_vector& rules = source.get_predicate_rules(*it);
+                expr_ref_vector fmls(m);
+                for (unsigned i = 0; i < rules.size(); ++i) {
+                    app* head = rules[i]->get_head();
+                    expr_ref_vector conj(m);
+                    for (unsigned j = 0; j < head->get_num_args(); ++j) {
+                        expr* arg = head->get_arg(j);
+                        if (!is_var(arg)) {
+                            conj.push_back(m.mk_eq(m.mk_var(j, m.get_sort(arg)), arg));
+                        }
+                    }                    
+                    fmls.push_back(m.mk_and(conj.size(), conj.c_ptr()));
+                }
+                expr_ref fml(m);
+                fml = m.mk_or(fmls.size(), fmls.c_ptr());
+                mc0->insert(*it, fml);
             }   
             m_context.add_model_converter(mc0);
         }

src/qe/qe_sat_tactic.cpp

@@ -226,7 +226,7 @@ namespace qe {
             return alloc(sat_tactic, m);
         }
 
-        ~sat_tactic() {
+        virtual ~sat_tactic() {
             for (unsigned i = 0; i < m_solvers.size(); ++i) {
                 dealloc(m_solvers[i]);
             }

src/smt/params/preprocessor_params.cpp

@@ -23,6 +23,7 @@ void preprocessor_params::updt_local_params(params_ref const & _p) {
     smt_params_helper p(_p);
     m_macro_finder            = p.macro_finder();
     m_pull_nested_quantifiers = p.pull_nested_quantifiers();
+    m_refine_inj_axiom        = p.refine_inj_axioms();
 }
 
 void preprocessor_params::updt_params(params_ref const & p) {

src/smt/params/smt_params_helper.pyg

@@ -14,6 +14,7 @@ def_module_params(module_name='smt',
                           ('delay_units', BOOL, False, 'if true then z3 will not restart when a unit clause is learned'),
                           ('delay_units_threshold', UINT, 32, 'maximum number of learned unit clauses before restarting, ingored if delay_units is false'),
                           ('pull_nested_quantifiers', BOOL, False, 'pull nested quantifiers'),
+                          ('refine_inj_axioms', BOOL, True, 'refine injectivity axioms'),
                           ('soft_timeout', UINT, 0, 'soft timeout (0 means no timeout)'),
                           ('mbqi', BOOL, True, 'model based quantifier instantiation (MBQI)'),
                           ('mbqi.max_cexs', UINT, 1, 'initial maximal number of counterexamples used in MBQI, each counterexample generates a quantifier instantiation'),

src/smt/proto_model/datatype_factory.cpp

@@ -20,6 +20,7 @@ Revision History:
 #include"proto_model.h"
 #include"ast_pp.h"
 #include"ast_ll_pp.h"
+#include"expr_functors.h"
 
 datatype_factory::datatype_factory(ast_manager & m, proto_model & md):
     struct_factory(m, m.mk_family_id("datatype"), md),
@@ -47,8 +48,10 @@ expr * datatype_factory::get_some_value(sort * s) {
 */
 expr * datatype_factory::get_last_fresh_value(sort * s) {
     expr * val = 0;
-    if (m_last_fresh_value.find(s, val))
+    if (m_last_fresh_value.find(s, val)) {
+        TRACE("datatype_factory", tout << "cached fresh value: " << mk_pp(val, m_manager) << "\n";);
         return val;
+    }
     value_set * set = get_value_set(s);
     if (set->empty())
         val = get_some_value(s);
@@ -59,6 +62,17 @@ expr * datatype_factory::get_last_fresh_value(sort * s) {
     return val;
 }
 
+bool datatype_factory::is_subterm_of_last_value(app* e) {
+    expr* last;
+    if (!m_last_fresh_value.find(m_manager.get_sort(e), last)) {
+        return false;
+    }
+    contains_app contains(m_manager, e);
+    bool result = contains(last);
+    TRACE("datatype_factory", tout << mk_pp(e, m_manager) << " in " << mk_pp(last, m_manager) << " " << result << "\n";);
+    return result;
+}
+
 /**
    \brief Create an almost fresh value. If s is recursive, then the result is not 0.
    It also updates m_last_fresh_value
@@ -105,11 +119,18 @@ expr * datatype_factory::get_almost_fresh_value(sort * s) {
             }
         }
         if (recursive || found_fresh_arg) {
-            expr * new_value = m_manager.mk_app(constructor, args.size(), args.c_ptr());
+            app * new_value = m_manager.mk_app(constructor, args.size(), args.c_ptr());
             SASSERT(!found_fresh_arg || !set->contains(new_value));
             register_value(new_value);
-            if (m_util.is_recursive(s))
+            if (m_util.is_recursive(s)) {
+                if (is_subterm_of_last_value(new_value)) {
+                    new_value = static_cast<app*>(m_last_fresh_value.find(s));
+                }
+                else {
                     m_last_fresh_value.insert(s, new_value);
+                }
+            }
+            TRACE("datatype_factory", tout << "almost fresh: " << mk_pp(new_value, m_manager) << "\n";);
             return new_value;
         }
     }
@@ -181,12 +202,20 @@ expr * datatype_factory::get_fresh_value(sort * s) {
                 expr_ref_vector args(m_manager);
                 bool found_sibling   = false;
                 unsigned num         = constructor->get_arity();
+                TRACE("datatype_factory", tout << "checking constructor: " << constructor->get_name() << "\n";);
                 for (unsigned i = 0; i < num; i++) {
                     sort * s_arg        = constructor->get_domain(i);
+                    TRACE("datatype_factory", tout << mk_pp(s, m_manager) << " " 
+                          << mk_pp(s_arg, m_manager) << " are_siblings " 
+                          << m_util.are_siblings(s, s_arg) << "  is_datatype " 
+                          << m_util.is_datatype(s_arg) << " found_sibling " 
+                          << found_sibling << "\n";);
                     if (!found_sibling && m_util.is_datatype(s_arg) && m_util.are_siblings(s, s_arg)) {
                         found_sibling = true;
                         expr * maybe_new_arg = get_almost_fresh_value(s_arg);
                         if (!maybe_new_arg) {
+                            TRACE("datatype_factory", 
+                                  tout << "no argument found for " << mk_pp(s_arg, m_manager) << "\n";);
                             maybe_new_arg = m_model.get_some_value(s_arg);
                             found_sibling = false;
                         }

src/smt/proto_model/datatype_factory.h

@@ -29,6 +29,8 @@ class datatype_factory : public struct_factory {
     expr * get_last_fresh_value(sort * s);
     expr * get_almost_fresh_value(sort * s);
 
+    bool is_subterm_of_last_value(app* e);
+
 public:
     datatype_factory(ast_manager & m, proto_model & md);
     virtual ~datatype_factory() {}

src/smt/proto_model/proto_model.cpp

@@ -247,6 +247,7 @@ bool proto_model::eval(expr * e, expr_ref & result, bool model_completion) {
                             new_t = mk_some_interp_for(f);
                         }
                         else {
+                            TRACE("model_eval", tout << f->get_name() << " is uninterpreted\n";);
                             is_ok = false;
                         }
                     }
@@ -294,6 +295,7 @@ bool proto_model::eval(expr * e, expr_ref & result, bool model_completion) {
                                 // f is an uninterpreted function, there is no need to use m_simplifier.mk_app
                                 new_t = m_manager.mk_app(f, num_args, args.c_ptr());
                                 trail.push_back(new_t);
+                                TRACE("model_eval", tout << f->get_name() << " is uninterpreted\n";);
                                 is_ok = false;
                             }
                         }
@@ -326,6 +328,7 @@ bool proto_model::eval(expr * e, expr_ref & result, bool model_completion) {
                 todo.pop_back();
                 break;
             case AST_QUANTIFIER: 
+                TRACE("model_eval", tout << "found quantifier\n" << mk_pp(a, m_manager) << "\n";);
                 is_ok = false; // evaluator does not handle quantifiers.
                 SASSERT(a != 0);
                 eval_cache.insert(a, a);

src/smt/smt_model_finder.cpp

@@ -396,7 +396,7 @@ namespace smt {
             
             // Support for evaluating expressions in the current model.
             proto_model *             m_model;
-            obj_map<expr, expr *>     m_eval_cache;
+            obj_map<expr, expr *>     m_eval_cache[2];            
             expr_ref_vector           m_eval_cache_range;
 
             ptr_vector<node>          m_root_nodes;
@@ -409,7 +409,8 @@ namespace smt {
             }
 
             void reset_eval_cache() {
-                m_eval_cache.reset();
+                m_eval_cache[0].reset();
+                m_eval_cache[1].reset();
                 m_eval_cache_range.reset();
             }
             
@@ -468,6 +469,7 @@ namespace smt {
 
             ~auf_solver() {
                 flush_nodes();
+                reset_eval_cache();
             }
         
             void set_context(context * ctx) {
@@ -547,7 +549,7 @@ namespace smt {
                         for (obj_map<expr, unsigned>::iterator it = elems.begin(); it != elems.end(); it++) {
                             expr * n     = it->m_key;
                             expr * n_val = eval(n, true);
-                            if (!m_manager.is_value(n_val))
+                            if (!n_val || !m_manager.is_value(n_val))
                                 to_delete.push_back(n);
                         }
                         for (ptr_vector<expr>::iterator it = to_delete.begin(); it != to_delete.end(); it++) {
@@ -569,16 +571,19 @@ namespace smt {
 
             virtual expr * eval(expr * n, bool model_completion) {
                 expr * r = 0;
-                if (m_eval_cache.find(n, r)) {
+                if (m_eval_cache[model_completion].find(n, r)) {
                     return r;
                 }
                 expr_ref tmp(m_manager);
-                if (!m_model->eval(n, tmp, model_completion)) 
+                if (!m_model->eval(n, tmp, model_completion)) {
                     r = 0;
-                else
+                    TRACE("model_finder", tout << "eval\n" << mk_pp(n, m_manager) << "\n-----> null\n";);
+                }
+                else {
                     r = tmp;
                     TRACE("model_finder", tout << "eval\n" << mk_pp(n, m_manager) << "\n----->\n" << mk_pp(r, m_manager) << "\n";);
-                m_eval_cache.insert(n, r);
+                }
+                m_eval_cache[model_completion].insert(n, r);
                 m_eval_cache_range.push_back(r);
                 return r;
             }

src/smt/smt_model_generator.cpp

@@ -102,6 +102,7 @@ namespace smt {
                     if (th && th->build_models()) {
                         if (r->get_th_var(th->get_id()) != null_theory_var) {
                             proc = th->mk_value(r, *this);
+                            SASSERT(proc);
                         }
                         else {
                             TRACE("model_bug", tout << "creating fresh value for #" << r->get_owner_id() << "\n";);
@@ -110,6 +111,7 @@ namespace smt {
                     }
                     else {
                         proc = mk_model_value(r);
+                        SASSERT(proc);
                     }
                 }
                 SASSERT(proc);

src/smt/theory_arith_eq.h

@@ -193,7 +193,7 @@ namespace smt {
             return true;
         }
 
-        if (!r.get_base_var() == x && x > y) {
+        if (r.get_base_var() != x && x > y) {
             std::swap(x, y);
             k.neg();
         }

src/smt/theory_dl.cpp

@@ -162,7 +162,7 @@ namespace smt {
             m.register_factory(alloc(dl_factory, m_util, m.get_model()));
         }
         
-        virtual smt::model_value_proc * mk_value(smt::enode * n) {
+        virtual smt::model_value_proc * mk_value(smt::enode * n, smt::model_generator&) {
             return alloc(dl_value_proc, *this, n);
         }
 
@@ -201,9 +201,8 @@ namespace smt {
             if(!m_reps.find(s, r) || !m_vals.find(s,v)) {
                 SASSERT(!m_reps.contains(s));
                 sort* bv = b().mk_sort(64);
-                // TBD: filter these from model.
+                r = m().mk_func_decl(m_util.get_family_id(), datalog::OP_DL_REP, 0, 0, 1, &s, bv);
-                r = m().mk_fresh_func_decl("rep",1, &s,bv);
+                v = m().mk_func_decl(m_util.get_family_id(), datalog::OP_DL_ABS, 0, 0, 1, &bv, s);
-                v = m().mk_fresh_func_decl("val",1, &bv,s);
                 m_reps.insert(s, r);
                 m_vals.insert(s, v);
                 add_trail(r);

src/util/scoped_timer.cpp

@@ -70,7 +70,9 @@ struct scoped_timer::imp {
     pthread_t        m_thread_id;
     pthread_attr_t   m_attributes;
     unsigned         m_interval;    
+    pthread_mutex_t  m_mutex;
     pthread_cond_t   m_condition_var;
+    struct timespec  m_end_time;
 #elif defined(_LINUX_) || defined(_FREEBSD_)
     // Linux & FreeBSD
     timer_t         m_timerid;
@@ -93,35 +95,15 @@ struct scoped_timer::imp {
     static void * thread_func(void * arg) {
         scoped_timer::imp * st = static_cast<scoped_timer::imp*>(arg);  
 
-        pthread_mutex_t  mutex;
+        pthread_mutex_lock(&st->m_mutex);
-        clock_serv_t host_clock;
-        struct timespec abstime;
-        mach_timespec_t now;
-        unsigned long long nano = static_cast<unsigned long long>(st->m_interval) * 1000000ull;
 
-        host_get_clock_service(mach_host_self(), CALENDAR_CLOCK, &host_clock);
+        int e = pthread_cond_timedwait(&st->m_condition_var, &st->m_mutex, &st->m_end_time);
-
-        if (pthread_mutex_init(&mutex, NULL) != 0)
-            throw default_exception("failed to initialize timer mutex");
-        if (pthread_cond_init(&st->m_condition_var, NULL) != 0)
-            throw default_exception("failed to initialize timer condition variable");
-
-        abstime.tv_sec  = nano / 1000000000ull;
-        abstime.tv_nsec = nano % 1000000000ull;
-
-        pthread_mutex_lock(&mutex);
-        clock_get_time(host_clock, &now);
-        ADD_MACH_TIMESPEC(&abstime, &now);
-        int e = pthread_cond_timedwait(&st->m_condition_var, &mutex, &abstime);
         if (e != 0 && e != ETIMEDOUT)
             throw default_exception("failed to start timed wait");
         st->m_eh->operator()();
-        pthread_mutex_unlock(&mutex);
 
-        if (pthread_mutex_destroy(&mutex) != 0)
+        pthread_mutex_unlock(&st->m_mutex);
-            throw default_exception("failed to destroy pthread mutex");
+
-        if (pthread_cond_destroy(&st->m_condition_var) != 0)
-            throw default_exception("failed to destroy pthread condition variable");
         return st;
     }
 #elif defined(_LINUX_) || defined(_FREEBSD_)
@@ -150,6 +132,22 @@ struct scoped_timer::imp {
         m_interval = ms;
         if (pthread_attr_init(&m_attributes) != 0)
             throw default_exception("failed to initialize timer thread attributes");
+        if (pthread_cond_init(&m_condition_var, NULL) != 0)
+            throw default_exception("failed to initialize timer condition variable");
+        if (pthread_mutex_init(&m_mutex, NULL) != 0)
+            throw default_exception("failed to initialize timer mutex");
+
+        clock_serv_t host_clock;
+        mach_timespec_t now;
+        unsigned long long nano = static_cast<unsigned long long>(m_interval) * 1000000ull;
+        
+        host_get_clock_service(mach_host_self(), CALENDAR_CLOCK, &host_clock);
+        m_end_time.tv_sec  = nano / 1000000000ull;
+        m_end_time.tv_nsec = nano % 1000000000ull;
+        clock_get_time(host_clock, &now);
+        ADD_MACH_TIMESPEC(&m_end_time, &now);
+
+
         if (pthread_create(&m_thread_id, &m_attributes, &thread_func, this) != 0)
             throw default_exception("failed to start timer thread");
 #elif defined(_LINUX_) || defined(_FREEBSD_)
@@ -183,9 +181,25 @@ struct scoped_timer::imp {
                               INVALID_HANDLE_VALUE);
 #elif defined(__APPLE__) && defined(__MACH__)
         // Mac OS X
-        pthread_cond_signal(&m_condition_var); // this is okay to fail
+
+        // If the waiting-thread is not up and waiting yet, 
+        // we can make sure that it finishes quickly by 
+        // setting the end-time to zero.
+        m_end_time.tv_sec = 0;
+        m_end_time.tv_nsec = 0;
+
+        // Otherwise it's already up and waiting, and
+        // we can send a signal on m_condition_var:
+        pthread_mutex_lock(&m_mutex);
+        pthread_cond_signal(&m_condition_var);
+        pthread_mutex_unlock(&m_mutex);
+
         if (pthread_join(m_thread_id, NULL) != 0)
             throw default_exception("failed to join thread");
+        if (pthread_mutex_destroy(&m_mutex) != 0)
+            throw default_exception("failed to destroy pthread mutex");
+        if (pthread_cond_destroy(&m_condition_var) != 0)
+            throw default_exception("failed to destroy pthread condition variable");
         if (pthread_attr_destroy(&m_attributes) != 0)
             throw default_exception("failed to destroy pthread attributes object");
 #elif defined(_LINUX_) || defined(_FREEBSD_)